Si_3N_4与Si_3N_4-hBN陶瓷配副在水润滑下的摩擦化学行为  

Tribochemical Behavior of Si_3N_4hBN Ceramic Materials with Water Lubrication

作　　者：陈威[1] 高义民[1] 居发亮[1] 汪勇[1] 

机构地区：[1]西安交通大学金属材料强度国家重点实验室,西安710049

出　　处：《西安交通大学学报》2009年第9期75-80,共6页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(50672074)

摘　　要：利用MMU-5G销-盘式端面磨损试验机考察了蒸馏水润滑条件下Si3N4-hBN(六方氮化硼)复合陶瓷与Si3N4陶瓷配副时的摩擦磨损性能,并分别采用扫描电子显微镜、激光扫描显微镜、X光电子能谱和X射线能谱分析了摩擦面的形貌和物质组成.结果表明:在滴定法水润滑条件下,Si3N4-hBN/Si3N4配副的摩擦因数随hBN含量的增加而显著降低,当hBN体积分数为20%时,摩擦因数降至0.01,Si3N4-hBN的磨损率接近0;在浸入法水润滑条件下,Si3N4-hBN/Si3N4配副的摩擦因数均降至0.01.在滴定法水润滑条件下,磨屑不易被水带走,当Si3N4-hBN与Si3N4配副摩擦时,由于Si3N4-hBN摩擦面上hBN偏聚区域发生脆性断裂和剥落而形成剥落坑,磨屑在剥落坑中堆积并氧化、水解,反应产物富集于剥落坑中,进而在摩擦表面形成含B2O3和SiO2的摩擦化学反应膜,从而保护了Si3N4-hBN和Si3N4摩擦面,使其变得光滑,为发生流体润滑提供了条件.The tribological behavior of Si3N4-hBN composites with different hexagonal boron nitride （hBN） volume fractions under distilled water lubrication was investigated. Water-lubricated sliding tests were conducted on a pin-on-disc tester. The results show that the addition of hBN into Si3N4 matrix significantly decreased the friction coefficient from 0.30 for Si3N4 against Si3N4 pair to 0.01 for Si3N4-20% hBN against SiaN4 pair under titrimetric water lubrication, and the friction coefficient of Si3 N4-hBN/Si3 N4 pair decreased to 0.01 in water. The morphological analysis and chemical characterization of the worn surfaces via scanning electron microscopy, laser scanning microscope, and X-ray photoelectron spectroscopy reveal that under titrimetric water lu- brication, the hBN in Si3N4-hBN spalled off during the wearing tests and the spalled pits formed on the wearing surface of Si3N4-hBN, and then the debris dropped into the pits to react with water, thus a tribochemical film formed on the wearing surface. The formation of the tribochemical film facilitated smoothing the surfaces of Si3 N4-hBN and Sis N4 to create a fine lubrication environment.

关 键 词：复合陶瓷 水润滑 剥落坑 摩擦化学反应膜 

分 类 号：TH117.13[机械工程—机械设计及理论]